Kartoffelkuchen
-
Posts
1,642 -
Joined
-
Last visited
Content Type
Profiles
Forums
Developer Articles
KSP2 Release Notes
Bug Reports
Posts posted by Kartoffelkuchen
-
-
10 minutes ago, Exoscientist said:
[ - snip - ]
So SpaceX still has not demonstrated the Raptor can relight reliably in flight. In fact, all the Starship landing tests and actual flight tests have shown it is not reliable after relight in flight.
Bob Clark
Funny that you say that. Because in the paragraph above your quoted text, it clearly says they conducted a successful boostback burn, and they did so with all engines igniting and running perfectly fine when looking at the webcast.
Looking at the final seconds of the booster, with these high roll rates, it is no wonder the engines didn't light succesfully. It's not hard to imagine that when it's rolling like that and fuel sloshing around inside the tanks, that fuel ports won't be able to draw any fuel reliably.
And to emphasize again, that is not a Raptor related issue, but more of a fuel systems and a 'how to prevent fuel sloshing' issue. So I'd like to call your "Raptors can't relight successfully" argument fully debunked now with that successful boostback burn, until we a re proven otherwise by SpaceX.
-
38 minutes ago, Spaceception said:
Is this where Rocketdyne was in 2006 with their integrated powerhead?
I loosely follow this thread and their updates, but the speed they're moving at sure is looking impressive. Getting the powerhead of such an engine to work probably has to be the most difficult task. I'm stoked for what's to come!
-
11 hours ago, Shpaget said:
From FAA
No words on whether anybody found anything on ERs.
Apparently some airlines did a voluntary inspection of the plugs and found loose and damaged bolts, leading to that FAA notice.
-
5 minutes ago, tater said:
Again, so what? Accepted practice would make SS/SH an expended rocket, and grossly more expensive. Accepted practice on a huge rocket in the 2020s? We have an example. SLS.
Answer my question above: Should SS/SH find itself in orbit in the next few flights, with flight testing proceeding as expected, losing vehicles on the recovery side until they sort out S1 landing, then S2 EDL, would a new company choose the "old way," or the SpaceX way, and why might they have reason to pick one over the other? Both would now be "industry practice" where the most recent version (SpaceX) is also the current most successful rocket company on the planet.
One, if you have to go back decades for an example in this case, it's a bad example. What was the Soviet CFD simulation work like? How about all their other detailed computer simulation? Oh, yeah, not a thing. Every single thing about the N1 comparison is unserious, IMO. Two, IFT-2 had no such problem on the booster. It was flawless until after MECO/sep. It failed a reuse/landing test—which other industry standard rocket unsuccessfully boosted back and attempted a test landing? Oh yeah, 100% of them failed this test since rockets. SLS core also blew up after sep, raining rocket parts in the south Pacific.
The only failure on IFT-2 that matters was the Ship. We have no idea what the actual failure was, so <shrug>. Engine? Plumbing? Something else?
Hey guys, my blocker for *individual persons* does not have the effect it should when all of you pick up on *the persons* arguments again and again.
I am by no means a moderator, but I think that literally all of the counterarguments have at least been made twice now. Perhaps just let the person post their statements into the void, until something with a bit more substance to it comes up?
-
1 hour ago, Nuke said:
we need bigger raptors, t-rex scale at least. then we have fewer points of failure.
We might need to go even bigger to make Starship truly reliable...
Kerbal OG's might remember
-
2 hours ago, Exoscientist said:
In this slowed down clip by Zack Golden you can see objects spewing out of the engine section. Judging by the 9 meter diameter of the booster, I would say these objects are 2 to 3 meters long, 6 to 10 feet. That almost certainly means it was an engine explosion:https://twitter.com/CSI_Starbase/status/1734783989871763768
Robert Clark
You are absolutely right, it almost certainly is an engine explosion we see here.
The question we've been discussing all this time is why it did happen, and the #1 source is likely not that it happened because of faulty engines, but because the engines didn't receive any more fuel.
See when that turbopump, spinning at dozens of thousands of RPM, is not filled by fuel any more which protects it from runaway, it will spin up even faster and disintegrate, making the engine fail.
SN8 and SN10 as mentioned above had a similar failure cascade: no fuel / bubbles in fuel, leading to the engine failure.
-
5 hours ago, Exoscientist said:
3, Raptor no more reliable now than before on relights:
Not again.
If your cars fuel pump breaks down and the engine stops working, would you say that the engine is unreliable?
- Yeah, an amateur who doesn't know about the subsystems required to run your engine perhaps would say that.
We still don't know with certainty what happened, so let's not start this discussion again, until we get a little more insight.
-
28 minutes ago, JoeSchmuckatelli said:
What does that get you? (First I'm hearing about this)
Probably a greater internal volume to use, and perhaps lower reentry thermal loading in the forward section due to the stubbier shape?
-
Can the engines gimbal? From the way they are integrated into the heatshield I'd assume they can't. So they'd have to resolve to shutting of the engine on the other side in case of a failure to balance the thrust.
Let's hope they have their engine reliability in check then! I'm >stoked to see this fly
-
1 hour ago, Cuky said:
As a comparison I would use the F1 engine from Saturn V... they were unable to go through any test without it going RUD, but by the time they got to operational status the bugs were ironed. out and they worked like a charm for the most part
We've had this exact discussion like two pages ago, what's the point about in discussing this again?
We know the engine is not as reliable as one could hope for with another flight test coming up soon. Some like the approach, others don't. Apparently SpaceX has the money to give their vehicle a go anyway and see what happens.
-
1 hour ago, .50calBMG said:
The difference here is that the raptor is a completely novel engine design that had never been flown before, so failures should be expected. They are also testing and iterating on every engine, with raptor 3s starting to show the fruits of that labor. Raptor 3s are proving that they are substantially more reliable than the 2s, which in turn are more reliable than the 1s. You can't point to a few failed engines early on in a test program and say they are unreliable and always will be.
Take a look at how long the RS-25s took to get right, and even after all those flights on the shuttle, sls had multiple failures with the same engines, so are those unreliable as well? Same goes for the F-1s
I think the point he's critizicing is that SpaceX choose to go ahead with the first orbital flight test, while they knew their engines still were pretty unreliable and the vehicle had a high chance of multiple engine failures / loss of control because of that.
No one blames them for exploding engines when they are still in development and are properly tested on the ground. However, knowingly sending your rocket up with engines which are likely to fail on ascent is a bit "meh". Obviously we don't have the full picture though. It could be that they were done simulating everything they can, and just had to know if their launch vehicle design worked as their simulations shown to progress their work. At some point you have to make that jump.
Still, I agree with him here that perhaps the test feels a bit rushed, and if they had spent a couple more months proving their engines work halfway reliable it would have greatly increased the chance of a successful first test flight.
-
Very lovely to see such a big interest in my work here.
I've stepped aside from modding for quite a while, but I'll see if I can cook something up for you guys once my time schedule eases up a bit in the next weeks.
-
3 hours ago, Exoscientist said:
Actually, they can. All it would take is someone, anyone in the European space community with the audacity to ask that one impertinent question, “How much would it cost to add a second Vulcain to the Ariane 5/6?”
Once that question is asked, and answered, it becomes obvious how to proceed to match SpaceX in low cost, reusability, and manned launchers.
Bob Clark
Could you please elaborate on your mystical answer?
In how far would adding a second Vulcain to the Ariane V or 6 be of any help in making it a more competitive launch vehicle, because I don't get what you are trying to imply.
-
24 minutes ago, AckSed said:
I... Excuse me? The flip was planned? They were going to do a supersonic hammer-throw with a building-sized rocket to avoid fitting a normal separation mechanism.
The HELL? This is Philip Bono levels of far-out. SpaceX, you have flabbered my gast most thoroughly, and I salute you.
Yeah, it's pretty nuts to think about. However, not as crazy from an aerodynamic perspective with air density and thus dynamic pressure being very, very low at that altitude and, compared to reentry velocities, low speed at stage seperation. I was much more worried about the aerodynamic stability during ascend leading up to Max-Q, since with the flaps being deployed, that will quickly generate a huge momentum if you deviate even just a little from your velocity vector.
When we're talking about the actual stage seperation mechanism, I'm not really sure what the benefits to doing it this flippy way would be, except for a lower structural mass. But I'm sure they have their reasons, or we will very quickly let them see switching their strategy. Rapid iteration in aerospace is always exciting to watch
-
Just now, tater said:
That was kerbal af
Like the thing just doing barrel rolls in 35km altitude? Soooo incredibly Kerbal, yeah. Not enough gimbal authority and too much lift in the front obviously, we all know it. /s
-
Aaaand FTS bringing us an end to the show!
-
Spinning a little out of control here huh
-
Holy sh*t it actually flies.
Looks like multiple engines out though, maybe intentional?
-
Holding at 40sec
-
43 minutes ago, tater said:
-
so basically another Falcon 9, when speaking of payload numbers and architecture. Interesting bet on that design.
-
11 hours ago, Gary Stewart said:
I second this. I'd love to have the Delta rocket family for Realism Overhaul in KSP 1.12.3.
Doesn't it work any more in 1.12.? I don't really know if there has been any impact on part mods which would prevent this from working between KSP 1.7 and KSP 1.12.
-
3 hours ago, tater said:
Excuse me, but "he"?
Rocket looks very cool though
-
Also, having the option to copy and paste a certain colour set from a part, onto another part would be great! It's very tiring to paint a certain number of parts this way, then paint some other parts in a different colour only to see that you forgot to paint some parts with the first colour. Then you have to go back and try to get that first colour again, which mostly results in having to repaint everything because you can't 100% get the previous colour again with the sliders.
-
A list of bugs I noted when building and flying around in my first built airliners, jet aircraft.
Control Surfaces on Angled Wings rotate off-axis in flight
How to reproduce:
- Attach any Wing to a craft, e.g. HPW-1000 "Evolution"
- Rotate the wing using the translation tool, for example upwards as seen on this image
- Launch craft and play with the controls
Wings don't change mass when adjusting its size
I mean...seriously? This was a feature in KSP 1 with the procedural fairings, so it shouldn't bee to hard to implement to make a wings mass depend on its span, thickness, width etc.
How to reproduce:
- Build any wing and watch the vessels total mass when changing its dimensions
Reverse thrust animation is broken when using action groups
When Action Group is toggled, the reverse animation of the J-90 "Goliath" Jet engine plays, then goes back to its base state (showing that the engine is not reversing), while the engines deliver reverse thrust. I'd need to check if this happens with the other jet engines too.
When using the right-click menu to toggle the reverse thrust, everything works.
How to reproduce:
- Attach J-90 "Goliath" Jet engine to aircraft
- Assign an action group to the action "Cycle Mode"
- Launch craft, activate engines, throttle up
- Enable the assigned action group and watch the animation play, then go backto its first frame
Another bug, related to this: While the reverse animation is playing, the thrust produced by the jet engine is not updated. Check right-click menu to see the thrust value.
SpaceX Discussion Thread
in Science & Spaceflight
Posted · Edited by Kartoffelkuchen
Hmm not really a fan of that stretching tbh. Sure it makes sense from a performance perspective, but it will also make the stack much more susceptible to weather and winds again I'd assume, which a SH/SS stack with a lower height/thickness ratio would probably not be. Especially with the aero devices.
Also, it makes Starship landings on another planet even more challenging as to not make it tip over, terrain will absolutely need to be flat and touchdown performed with very little to none horizontal velocity, as long as the leg design doesn't change. It probably wouldn't be able to take the more "sloppy" F9 booster landings we've seen with the bounces. Especially since the COM will be even higher with the header tank being used for landing too. Astronaut boarding / cargo unloading on other bodies will also get interesting.